The present invention relates to a dishwasher comprising a washing compartment for accommodating items to be washed and a first circulation circuit for subjecting items to be washed in the washing compartment to a washing liquid, wherein the first circulation circuit has a circulation pump for circulating the washing liquid, a water heater for heating the circulated washing liquid, and a spraying device for spraying the items to be washed with the circulated washing liquid, wherein in the first circulation circuit the washing liquid is routed from the washing compartment to the circulation pump and fed back into the washing compartment via the spraying device.
A dishwasher having such a circulation circuit is known from experience. In such a dishwasher, the items to be washed are subjected to washing liquid in a washing compartment, i.e. washing liquid which collects in a collection sump of the washing compartment is extracted by means of a circulation pump and is pumped back into the washing compartment via a spraying device. In this case, any required heating of the washing liquid is done by means of a water heater, this being arranged in the circulation circuit, at the same time as the items to be washed are subjected to the washing liquid.
However, the known dishwasher has the disadvantage that any heating of a washing liquid entails a warming of the washing compartment and/or the items to be washed that are located therein. Therefore, if the washing liquid to be warmed is not intended for immediate application to items to be washed, this results in unnecessary energy consumption and consequently in low efficiency of the dishwasher.